HMHaga - C5 Z06 nuts and bolts

Don't drive with your nannies on! With active handling in competitive driving mode, yaw control is still active and using the rear brakes to correct excessive yaw on corner entry/exit. This causes the rear brakes to run hot, and in my case one of the rotors cracked as it cooled down in the pit. I even heard the *PING* as it happened. To prove the point, I drove a session with TC and AH disabled, and spun the car exiting a corner. Coming from a Lotus Elise I've developed a habit of mashing the throttle on corner exit, as there never is too much throttle with an 1800 cc mid-engined car. 305 to 330 mm brake rotor After some research online, I found that the C6 with the Z51 option code uses a larger 330 mm brake rotor, but still share the same caliper and parking brake dimensions.  Plus Increased thermal capacity. The EBC Z51 rotors are ventilated on both sides, have a higher mass and increase the swept diameter of the brake pad Better looks, the brakes fill the 18" wheel and

High up in the mountains in Norway, close to freezing temperatures, the driver side window regulator broke down. Perfect timing. Fortunately, I managed to pull the window up by assisting the motor. A broken piece of plastic was all it took I had to twist my brain to get the parts back in the correct orientation. Notice that as pictured, it will not work. The wire coming from left (door B pillar) needs to pass below the right wire, otherwise it will conflict with the window. Mounted incorrectly here: I also noticed that the regulator power cable and the door latch switch cables interfered with the mechanism as it moved up and down. so I used some high strength duct tape to move them out of the way. New window regulator in place. I ran the window all the way down so that there wasn't any tension on the mechanism before tightening the bottom nuts. I followed Chris Askew's guide to replace the regulator:  https://www.chrisaskew.net/blog/2020/12/8/how-to-replace-window-regulator-200

With a large oil cooler in front of the radiator, I noticed that the water temperature exceeded 115 °C. At such temperatures, the ECU starts to pull timing to reduce engine power output. I resealed the radiator shroud, cleaned out debris, installed a 160  thermostat (71 °C) and lowered the fan settings with HP tuners, but this was still an issue. The stock radiator had developed a hairline crack in the plastic end tank, which I discovered by luck when running the engine without the radiator and the fan shroud removed. A DeWitts or Ron Davis radiator was my preferred solution, but after adding shipment costs and import taxes the total was above $1000. I decided to go for the less expensive Engineering Cooling Products (ECP) radiator for the C5. The ECP radiator arrived without any visible damage, which is always a risk when having fragile parts transported long distance. I bought it with a consumable electrode, to replace the flimsy petcock supplied.  The radiator installed nicely and s

On the first track day with the Z06, the clutch pedal stuck to the floor and had to be pulled up. This only became worse with time, and the clutch pedal would get stuck as soon as I tried shifting at high RPMs. I tried the "ranger method" numerous times, but it didn't help. Gearshifts were also harsh, so I though that the synchronizers were bad as well.  I was about to start pulling down the exhaust etc to access the bleed screw, and purchase a Tick Master Cylinder, but then I found this thread: Clutch bleeding from the mc I figured I should give it a try: I filled the reservoir with new fluid and used a fitting delivered with the MityVac. As you can see, a lot of air pockets and old fluid was released! While at it, I also performed the following: Removed clutch pedal assist springs Refilled with high temp brake fluid (Castrol React Performance DOT 4) Added heat insulation to the clutch line, which is passing right below the exhaust manifold (I released the line from the

Spring from an old welding cable, which helps to push up the boot lid when opened. 

The GM key fob has no tactile feedback, it reacts slowly and the rubber caps wear out. Fortunately, someone has reprogrammed VW key fobs to work with GM cars - and the Corvette C5. You have to cut the shaft of the stock key. Make sure that you don't cut too far down, otherwise the key will not fully enter the ignition lock - making it impossible to turn the key (BTDT). More information and links to e-bay on the Corvette Forums

Oily bottom end With an oil pan soaked in oil, it was time for repairs.  I had planned to replace the harmonic balancer with an ATI underdrive unit, but it was simply too expensive after adding shipping costs and 25% VAT. I decided on an OEM PB1117N Dayco balancer. Ouch, what a mess I found non-factory sealant between the front cover edge and the oil pan, so someone has previously serviced the engine. They obviously didn't care about centering the front cover and seal, which resulted in uneven wear of the seal, which again wore down the sealing surfaces of the harmonic balancer. To avoid a revisit later on, I decided to change all other parts that could be causing an oil or water leak in this area. Front cover gasket, water pump gaskets, front end seal. The lower oil pan gasket was changed last year. Removing and reinstalling harmonic balancer The first attempt at removing the balancer failed. I retried with a stronger puller with a sharp end tip, which would secure itself securely

I came across a spreadsheet on corvetteforum.com with reported valve spring failures linked to the car build date. My 2003 with yellow valve springs was right in the sweet spot for a failure, which is not a good mix with track day usage and high RPMs. I decided to use the blue GM Performance valve springs, as I didn't (and don't) have any immediate plans for a cam upgrade. To prevent valves from dropping after removing the retainers, I coiled up a rope through the plug hole and then rotated each cylinder towards TDC. When the breaker bar resisted rotation, I knew that the rope was pushing on the valves. I then removed the retainers using a magnetic tool and a light tap with a plastic hammer.  While the valve springs are out, it would be dumb not to change the valve stem seals as well. The seals were easily removed using a plier, and I simply pushed the new seals on using a valve spring. I checked the valve gear for wear. The tappets looked almost like new, and I couldn't fi

While disassembling parts of the dash and center console to repair the HVAC display, large pieces of brittle plastic disintegrated. To assemble the parts again, the plastic would need repairs.  Using a soldering iron, a Dremel tool and some leftover ABS plastic and zip ties as additional material, the cracked pieces were rebuilt.  The piece above the thermistor/air temperature sensor was broken off and missing, and was rebuilt by cutting out a similar profile from a piece of plastic. By melting deep into the original plastic piece, the new plastic bonds nicely.  Dremel tool and soldering iron used to repair the broken plastic pieces Repairs finished